Dear Peter. I am sending you the final results of TPC testing under the pressure P=10.15Bar. These data have been obtained in the second half of May 18. After that TPC irradiated by 90Sr source under HV=6kV during two days. In totally it means that TPC worked properly during one week under the source current 30nA and HV=5.8kV(for P=9.7Bar) and HV=6kV (for P=10.15Bar). I would like to point out that it necessary to perform more care TPC investigation in the future. In a frame of this work it is necessary to investigate the current counting rate behavior for each anode wire and cathode strip. In addition I propose to investigate an electron efficiency in TPC. For this purpose I would like to organize trigger (GATE) from that electrons which passed through TPC and to measure coincidence with pulses from the wires that are placed closer to the entrance Be-window. My best regards. Anatoly > Dear Peter. > Below you can find a file with preliminary results of TPC testing in > hydrogen. Unfortunately the pressure inside of vessel is go down day per > day because of leak of the valve. For instance, today pressure is 9.58 > Bar. > > Please note, high voltage values indicated in figures have NOT corrected > according to the pressure values. It means that high voltage 5.8kV will > correspond to the HV=6.0kV under the pressure P=10Bar. > > To be sure that TPC has some "long time stability" (at list a few days) > two days ago the TPC run started under HV=5.8kV with 90Sr. During this > period pressure was changed between 9.7 and 9.6Bar. Till now TPC is > running properly. This test will be finished by Friday - Volodja's leaving > day. > > As one can see TPC can detect an electron tracks from 90Sr. Signal/noise > ratio is more than 10. > > Of cause we have some quite serious questions for the long term stability > TPC and would like to improve it. More detail report we will send you > late. > > My best regards. > Anatoly > > > > > > > > >
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TPC report_180505.doc
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